gistfile1.js

db.query('SELECT 1')
  ('result1', function(result1) {
    return db.query('SELECT 2');
  })
  ('result2', function(result2) {
    return db.query('SELECT 3');
  })
  ('result3')
  .addCallback(function(results) {
    p(results); // == {result1: result1, result2: result2, result3: result}
  })
  .addErrback(function() {
   // If anything goes wrong in this chain, catch it here!
  });